Spectrometric and Photographic Analysis of a Laser-Produced Hydrogen Plasma.

Abstract

Light from a neodymium glass laser was focused in hydrogen gas at pressures from 20 mTorrs to 9.16 atm in order to produce optical breakdown. The forward scattered light from the breakdown region was spectrally analyzed with a grating spectrograph from 10,300 to 10,900 A. It was found that the spectral distributions exhibited no distinguishable frequency shift. However, the absorption of the laser light depended on frequency and gas pressure. The time dependence of the onset of absorption was determined by comparing the cell beam with a beam-splitted reference beam that bypassed the pressure cell. The light scattered at an angle of 90 was photographed with a high speed image converter camera in the framing mode. This revealed evidence of self-focusing during the time the laser light was on. The plasma parameters were calculated from the kinetic theory of ideal gases and the theory of ionized gases, assuming complete ionization. (Modified author abstract)

Document Details

Document Type
Technical Report
Publication Date
Jun 01, 1973
Accession Number
AD0764496

Entities

People

  • Kurt D. Wachsmuth

Organizations

  • Naval Postgraduate School

Tags

DTIC Thesaurus Topics

  • Absorption
  • Converters
  • Frequency
  • Frequency Shift
  • Gases
  • Glass Lasers
  • Hydrogen
  • Image Converters
  • Images
  • Ionization
  • Ionized Gases
  • Kinetic Theory
  • Lasers
  • Nd:Glass Lasers
  • Photographic Analysis
  • Time Dependence

Fields of Study

  • Engineering
  • Physics

Readers

  • Combustion science or combustion engineering.
  • Pulsed Power and Plasma Physics.
  • Spectroscopy.

Technology Areas

  • Directed Energy
  • Directed Energy - Lasers